JP2545159B2 - Music synthesizer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a musical tone synthesizer to which a digital electronic circuit such as an electronic piano or a synthesizer is applied.

2. Description of the Related Art In recent years, due to advances in digital technology, many musical tone synthesizers have been developed that apply digital electronic circuits such as electronic pianos and synthesizers. Among them, a musical tone synthesizer has been proposed which synthesizes musical tones by an arithmetic circuit using delay means (for example, Japanese Patent Laid-Open No. 59-187398 “Wavetable changing device and method for generating musical tones”).

A conventional tone synthesizer will be described below with reference to the drawings.

FIG. 2 is a block diagram of a conventional tone synthesizer. The musical sound synthesizer shown in FIG. 2 is capable of faithfully synthesizing the sound of a string-plucking musical instrument such as the guitar shown in FIG.

The conventional musical sound synthesizer comprises a memory 21 in which drive waveform data is stored in advance, and a counter 22 which reads the drive waveform data stored in the memory 21 according to the input sound generation start information kon at the timing of generation of the shift clock sck. Drive waveform generating means 101, selecting means 102 comprising a selector 23 for selecting the drive waveform data and waveform data read from the memory 21 and outputting the selection result as tone data,
Shift clock sck for data input from selector 23
The delay means 103 consisting of a shift register 24 that shifts at each generation timing to delay for a fixed time, a multiplier 25 that multiplies the data output from the shift register 24 by a value 0.5, and the data output from the shift register 24. Delays 1 sampling clock (corresponding to a shift clock), a multiplier 27 that multiplies the data output from the delay device 26 and the value 0.5, and the addition of the data output from the multipliers 25, 27 And outputs to selector 23
The calculation means 104 is composed of 28. The calculation means 104 constitutes a first-order low-pass filter, and the selection means 10
The data circulating in the loop-shaped circuit composed of 2, the delay means 103, and the arithmetic means 104 are collectively referred to as waveform data.

FIG. 3 is a schematic view showing a sounding mechanism of a string-plucking type musical instrument (for example, a guitar).

In FIG. 3, the string 3 stretched by the nut 1 and the bridge 2 on the body 5 is supported by the fret 4 on the body 5 and the bridge 2 by the pressing of the finger A. The string 3 vibrates when it is flipped by the finger B,
Musical sound is generated. More specifically, by striking the string with the finger B, the acceleration is input to the point where the string is played.
After that, the acceleration propagates through the string 3, is reflected by the fret 4 and the bridge 2, and returns to the place where the finger B has played the ball again.
By repeating this operation, the string 3 vibrates and a musical sound is generated. The musical tone synthesizer shown in FIG. 2 approximately realizes this operation using a digital electronic circuit.

FIG. 4 shows an example of the musical sound envelope of the musical instrument (eg, guitar) of the string-plucking type shown in FIG. 3, where (A) is time t _0.
In vibrations of the strings 3 caused by playing the chord, the tone when abruptly attenuated the vibrations of the strings 3 at time t ₁ envelope, string 3 by playing the string 3 with (B) the time t ₁ Envelope of musical sound data when vibration occurs, (C) is an envelope of synthesized values of musical sounds of (A) and (B), and (D) is vibration of the string 3 by playing the string at time t ₀ . The envelope of the musical sound in the case, (E) is the envelope of the musical sound data when the vibration of the string 3 is generated by playing the string 3 at time t ₁ , and (F) is the synthesized value of the musical sounds of (D) and (E). Is the envelope of. (C) represents the envelope of the musical sound when the finger A is pressed down again, for example, every time a finger B is pressed by the musical instrument (eg, guitar) of the type that plays the strings 3 shown in FIG. The flipping operation with the finger B corresponds to the times t ₀ and t ₁ , and the finger A is re-pressed immediately before the flipping operation at t ₁ and the string 3
This is the case when the vibration of is stopped. On the other hand, (F)
In the musical instrument (eg, guitar) of the type that plays the strings 3 shown in FIG.
It represents the envelope of the musical sound when not pressing again.
The flip operation with the finger B corresponds to times t ₀ and t ₁ . Since the remaining vibrations of the strings 3 caused by plucking at time t ₀ since no re pressing a finger A at time t ₁ ((time t ₁ after the envelope D)), and play the strings 3 at time t ₁ (Envelope of (E)), (D)
And (E) are synthesized tones, that is, an envelope of (F).

The operation of the conventional tone synthesizer configured as above will be described below.

First, when the pronunciation start information kon reaches the value 1, the counter 22
Resets the count value (address of the memory 21) to the value 0, then counts up the count value at the generation timing of the shift clock SCK, and reads the memory 21 each time. Here, the counter 22 addresses the entire area of the memory 21 from the value 0, and then holds the count value when the final address of the memory 21 is reached. The memory 21 stores the data corresponding to the acceleration given to the strings by playing the strings 3 as described above, and is input to the A input of the selector 23 by the reading operation of the counter 22. The value 0 is stored in the final address of the memory 21, so the count value of the counter 22 is stored in the memory 21.
The value 0 is continuously output as the drive waveform data after the time when the last address of the drive address is reached. Selector 23 is memory 21
It is assumed that the A input is selected until all the drive waveform data stored in is read, and then the B input is selected. The drive waveform data is input to the shift register 24 via the selector 23 and is output as desired musical tone data. In the shift register 24, the shift clock SC
The input data is shifted at every generation timing of K (corresponding to the sampling clock), and is shifted by the word length of the shift register 24 before being output. Therefore, if the sampling period is Ts and the word length of the shift register 24 is M, the period T of the tone data is T = Ts × M (1) The operation of the shift register 24 corresponds to the propagation operation in which the acceleration input from the finger B to the string propagates through the string in the schematic diagram of FIG. 4, and the time when the acceleration reciprocates the string is (1) It corresponds to the period T of the equation.

The waveform data output from the shift register 24 is cut off in the high frequency range by the calculating means 104. The calculation means 104 performs a generally known first-order FIR filter operation, and the transfer function H (z) of the filter is given by the following equation (2).

H (z) = (1 + z ⁻¹ ) / 2 (2) The waveform data output from the calculating means is B of the selector 23.
Entered in the input. Here, if the word length of the memory 21 is N, the following equation (3) has a relationship with the word length M of the shift register 24.

N <M (3) Therefore, after the sample value x of the drive waveform data inputted from the memory 21 is processed by the circuit composed of the selecting means 23, the delay means 103 and the calculating means 104, the selector 2 is again operated.
When the waveform data is input to the B input 3 of 3, the selector 23 selects the B input. The drive waveform data output from the drive waveform generating means 101 as described above circulates in a loop circuit composed of the selecting means 102, the delay means 103, and the calculating means 104. Due to this cyclic operation, the high frequency component of the waveform data is gradually cut off by the calculating means 104. This corresponds to an operation in which the high-frequency component of the acceleration propagating through the string 3 is absorbed by the body 5 in the nut 1 and the bridge 2 in the schematic view of FIG.

However, in the above-described conventional configuration, when the sound generation start information kon becomes the value 1 (when sound generation start is instructed), the drive waveform data (musical sound data Since the initial waveform data) comes at the beginning of the musical tone data, only the same tone color is output each time. Therefore, the musical tone as shown in FIG. 4 (C), that is, the musical tone generated by the playing method of pressing the string A again each time the string B is played with the finger B in the musical instrument of the type playing the string 3 in FIG. In addition, in a musical tone as shown in FIG. 4 (F), that is, in a musical instrument of the type that plays the string 3 in FIG. 3, for example, a playing method in which the finger B is continuously played while the finger A is always held down. It is not possible to properly use the musical sound generated by
There is always a problem that only the musical sound as shown in FIG. 4C can be synthesized.

The present invention solves the above problems, and an object of the present invention is to provide a musical tone synthesizer capable of selectively using musical tones according to the way of playing like an actual musical instrument.

Means for Solving the Problems In order to solve the above problems, the musical tone synthesizing apparatus of the present invention includes a driving waveform generating means for generating and outputting driving waveform data according to a sound generation start instruction signal, and at least a delay device and a gate circuit. A loop circuit having a closed-loop circuit including the circuit, wherein the driving waveform data supplied from the driving waveform generating circuit is circulated to take out the circulated data as desired musical tone data; and the gate circuit of the loop circuit is opened and closed. Resetting means for selectively resetting the data circulating through the loop means by performing control, wherein the resetting means resets the loop means from the time of generation of the tone generation start instruction signal when there is a reset instruction. By closing the gate circuit in the loop means for a time corresponding to the delay time of the constituent delay device, the tone generation start instruction signal All the data circulating in the loop means before the occurrence are reset.

Operation With the above configuration, when two drive waveform data are continuously input to the loop means including the delay device and the gate circuit to generate two musical tone data (preceding tone and succeeding tone, respectively), resetting is performed. When the means does not give a reset instruction, the preceding sound (remaining in the delay circuit in the closed loop) is overlaid on the succeeding sound when the succeeding sound is sounded,
When the reset means gives a reset instruction, the gate circuit closes for the delay time of the delay device and resets the data accumulated in the delay device before the sounding time of the subsequent sound to the value 0.
First, the preceding sound is reset and then the following sound is generated. That is, when synthesizing the musical tone of FIG. 4 (C), the waveform data is reset to the value 0 at the timing when the sound generation start instruction is issued by the resetting means, and then the waveform of FIG.
In the case of synthesizing the musical tone, the desired musical tone data can be obtained by not performing the reset operation by the resetting means.

Embodiment One embodiment of the present invention will be described below with reference to the drawings. The same components as those shown in FIG. 2 of the conventional example are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 is a block diagram of the musical sound synthesizer of the present invention.

The tone synthesizer of the present invention is a selector of the conventional example shown in FIG.
Instead of 23, addition means 201 including an adder 11 for adding the drive waveform data output from the memory 21 and the waveform data
And the output signal of the one-shot circuit 13 and the one-shot circuit 13 for transmitting the value 1 for a time (Ts × M time) corresponding to the word length M of the shift register 24 when the pronunciation start information kon becomes the value 1. An AND gate 14 that inputs a reset flag and outputs a reset flag when the sound generation start information kon has a value of 1 and an AND gate 12 that resets the data output from the adder 28 when the output signal of the AND gate 14 has a value of 0 It is configured by adding a reset means 202 composed of and.

Regarding the musical sound synthesizer configured as described above,
The operation will be described below with reference to FIGS. 3, 3 and 4. The basic operation of the musical tone synthesizer shown in FIG. 1 is the same as that of the conventional musical tone synthesizer shown in FIG.

First, in a musical tone as shown in FIG. 4C, that is, in a musical instrument of the type that plays the string 3 in FIG.
The operation of synthesizing a musical tone generated by a playing method in which the finger A is pressed again each time the string 3 is played with is explained. In this case, it is necessary to mute the musical sound data before sounding. The reset means 20 performs this operation.
Is 2. When the new sound generation start information kon becomes the value 1, the output of the one-shot circuit 13 becomes the value 1 for Ts × M time, and at this time, the reset flag is input to the AND gate 12 via the AND gate 14. In this case, the reset flag has a value of 1. Therefore, the AND gate 12 resets the waveform data while the output of the one-shot circuit 13 has the value 1. That is, the shift register
Since all the waveform data remaining in 24 are reset to 0, the envelope of the musical sound data synthesized from the time when the pronunciation start information kon newly becomes 1 (time t _{1 in} FIG. 4C). Is as shown in FIG.

Next, a musical tone as shown in FIG.
An operation of synthesizing a musical tone generated by a playing method in which the finger B is continuously pressed in the musical instrument of the type of playing the strings 3 shown in FIG. 3 is continuously described. In this case, it is not necessary to mute the musical sound data before sounding. Therefore, the reset means 20
In 2, reset operation is not performed. The one-shot circuit 13 when the new pronunciation start information kon becomes the value 1
Has a value of 1 for Ts × M time, and the reset flag is input to the AND gate 12 via the AND gate 14 at this time. In this case, the reset flag has a value of 0. Therefore, regardless of the value of the output signal of the one-shot circuit 13, the value output from the AND gate 14 is 0, so the AND gate 12 does not reset the waveform data. That is, since the waveform data remaining in the shift register 24 is added to the drive waveform data in the adder 11, the time point when the tone generation start information kon newly becomes 1 (t in FIG. 4C).
The envelope of the musical sound data synthesized from ₁ time) is as shown in (F) of FIG.

As described above, according to this embodiment, in the musical tone as shown in FIG. 4C, that is, in the musical instrument of the type in which the string 3 in FIG. Musical sounds generated by playing methods such as pressing again,
A musical tone as shown in FIG. 4 (F), that is, a musical tone produced by a musical instrument of the type of plucking the strings 3 shown in FIG. Can also be synthesized.

In the present embodiment, the delay means 103 is composed of a shift register, but it is generally known that the delay means 103 can be composed of a memory. Also, the addition means 20
The loop-shaped circuit composed of 1, the delay means 103, the arithmetic means 104, and the reset means 202 does not matter even if the connection order of them is changed. Further, although the position at which the musical tone data is taken out is after the adding means, it does not matter even after the delay means 103, after the arithmetic means 104, or after the reset means 202.

EFFECTS OF THE INVENTION As described above, according to the present invention, it is possible to generate the preceding sound and the following sound in an overlapping manner with only one sounding module (one closed loop), that is, without providing a plurality of sounding modules. , It is possible to selectively perform whether the preceding sound is reset to be muted, and then a new sound is generated.

[Brief description of drawings]

FIG. 1 is a block diagram of a musical tone synthesizer in one embodiment of the present invention, FIG. 2 is a block diagram of a conventional musical tone synthesizer, and FIG.
The figure is a schematic diagram showing a sounding mechanism of a string-plucking type musical instrument (for example, a guitar), and FIGS.
It is a state diagram which shows the example of the musical tone envelope of the musical instrument (for example, guitar) of the type | form which plays the string shown in the figure. 101 ... Drive waveform generating means, 103 ... delaying means, 104 ... computing means, 201 ... adding means, 202 ... resetting means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuhiko Hayashi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Masahiko Hatanaka, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. Within

Claims (1)

(57) [Claims] 1. A drive waveform generating means for generating and outputting drive waveform data in response to a sound generation start instruction signal, and a closed loop circuit including at least a delay device and a gate circuit, which are supplied from the drive waveform generating means. Loop means for circulating the generated driving waveform data to take out the circulating data as desired musical tone data, and selectively opening and closing the data circulating through the loop means by controlling the opening and closing of the gate circuit of the loop means. Resetting means for resetting the loop, the resetting means, when there is a reset instruction, from the time of generation of the sound generation start instruction signal, during the time corresponding to the delay time of the delay device constituting the loop means, the loop By closing the gate circuit in the means, all the data circulating in the loop means before the generation of the sounding start instruction signal is reset. Musical tone synthesizing apparatus which is characterized in that bets.